About nine facilities in Germany would be closed or partially closed, but overall US troop numbers in the country were expected to increase a few hundred, according to the statement. In Portugal, some 500 US military and civilian personnel would be withdrawn from Lajes Field in the Azores.

"These actions will result in a slight decrease in our force levels, but will also ensure they are most effectively positioned to enable the US and our NATO allies to respond quickly to crises worldwide," the statement said.

"Additionally, these actions will result in the greater efficiency and effectiveness of our presence in Europe by reducing the US footprint while ensuring that the infrastructure in place will continue -- now and into the future -- to sustain US interests and support our partners in the region," it said.

The transformation of the infrastructure will help maximize US military capabilities in Europe and help strengthen America's important European partnerships, US Defense Secretary Chuck Hagel said in the statement.

The Pentagon has been systematically taking US forces out of Europe in recent years, reflecting the ongoing decrease in the size of the Army and Marine Corps as well as the increased emphasis on the Pacific and a desire to shift additional troops into Eastern Europe and other regions where tensions with Russia have grown.